Editing Heinrich Anton de Bary (section)

==Later career and research==
In 1867, de Bary moved to the [[University of Halle]] as successor to Professor [[Diederich Franz Leonhard von Schlechtendal]], who, with [[Hugo von Mohl]], co-founded the pioneer botanical journal ''Botanische Zeitung''. De Bary became its coeditor and later sole editor.  As an editor of and contributor to the journal, he exercised great influence upon the development of botany. Following the [[Franco-Prussian War]] (1870–1871), de Bary took the position of professor of botany at the [[University of Strasbourg]],<ref name="Robinson"/> where he was the director of the [[Jardin botanique de l'Université de Strasbourg]], and founder of its New Garden.<ref name="Deluzarche">{{cite journal |last1=Deluzarche |first1=Françoise |last2=Tournay |first2=Frédéric |title=Les débuts du nouveau jardin botanique de Strasbourg à travers le cahier d'inventaire de 1875 et les échantillons de l'herbier de Strasbourg |journal=Le Journal de Botanique |date=2012 |volume=60 |issue=1 |pages=3–45 |doi=10.3406/jobot.2012.1160 |s2cid=257316357 |url=https://www.persee.fr/doc/jobot_1280-8202_2012_num_60_1_1160 |access-date=23 March 2023}}</ref><ref>{{cite web |title=Botanical garden |url=https://int.strasbourg.eu/place/-/entity/sig/1085_ENV_267 |website=int.strasbourg.eu}}</ref> He was also elected as the inaugural [[Rector (academia)#Germany|rector]] of the reorganized university.<ref name="Robinson"/> He conducted much research in the university botanical institute, attracted many international students, and made a large contribution to the development of botany.<ref name="Horsfall"/><ref>{{cite book |last1=Chung |first1=King-Thom |title=Pioneers in microbiology : the human side of science |date=2018 |publisher=World Scientific |location=Singapore |isbn=9789813200364}}</ref>

His 1884 book ''Vergleichende Morphologie und Biologie der Pilze, Mycetozoen und Bakterien'' was translated into English as ''Comparative Morphology and Biology of the Fungi, Mycetozoa, and Bacteria'' ([[Clarendon Press]], 1887).<ref>{{cite journal|title=Review of ''Comparative Morphology and Biology of the Fungi, Mycetozoa, and Bacteria'' by A. de Bary|journal=The Saturday Review of Politics, Literature, Science, and Art|date=October 15, 1887|volume=64|issue=1668|pages=527–528|url=https://books.google.com/books?id=5Xc_AQAAIAAJ&pg=PA527}}</ref>

===Fungi and plant diseases===
De Bary was devoted to the study of the life history of [[fungi]]. At that time, various fungi were still considered to arise via spontaneous generation.<ref name="Horsfall"/> He proved that pathogenic fungi were like other plants, and not the products of secretions from sick cells.<ref name="Robinson"/>

In de Bary’s time, potato late blight had caused sweeping crop devastation and economic loss.  The origin of such plant diseases was not known at that time.  de Bary studied the pathogen ''[[Phytophthora infestans]]'' (formerly ''Peronospora infestans'') and elucidated its life cycle.<ref name="Horsfall"/>  [[Miles Joseph Berkeley]] (1803–1889) had insisted in 1841 that the [[oomycete]] found in [[potato blight]] caused the disease. Similarly, de Bary asserted that rust and smut fungi caused the pathological changes that affected diseased plants. He concluded that [[Uredinales]] and [[Ustilaginales]] were [[parasite]]s.<ref name="Robinson"/>

De Bary spent much time studying the morphology of fungi and noticed that certain forms that were classed as separate species were actually successive stages of development of the same organism. De Bary studied the developmental history of [[Myxogastria|Myxomycetes]] (slime molds), and thought it was necessary to reclassify the lower animals. He first coined the term [[Mycetozoa]] to include lower animals and slime molds. In his work on Myxomycetes (1858), he pointed out that at one stage of their life cycle (the [[plasmodia]]l stage), they were nearly-formless, motile masses of a substance that [[Félix Dujardin]] (1801–1860) had called [[Amoeba#Amoebae as organisms|sarcode]] ([[protoplasm]]). This is the fundamental basis of the protoplasmic theory of life.<ref name="Robinson"/>

De Bary was the first to demonstrate [[Fungus#Sexual reproduction|sexuality in fungi]]. In 1858, he had observed conjugation in the alga ''[[Spirogyra]]'', and in 1861, he described sexual reproduction in the fungus ''[[Peronospora]]'' sp. He saw the importance of observing pathogens throughout their whole life cycle and attempted to follow that practice in his studies of living host plants.<ref name="Robinson"/>

====Peronosporeae====
De Bary published his first work on potato blight  fungi in 1861, and then spent more than 15 years studying Peronosporeae, particularly ''Phytophthora infestans'' (formerly ''Peronospora infestans'') and ''[[Albugo candida|Cystopus]]'' (''[[Albugo]]''), parasites of [[potato]]. In his published work in 1863 entitled "Recherches sur le developpement de quelques champignons parasites", he reported inoculating healthy potato leaves with spores of ''P. infestans''.  He observed that mycelium  penetrated the leaf and affected the tissue, forming [[conidia]] and the black spots characteristic of potato blight. He did similar experiments on [[tuber]]s and potato stalks. He watched conidia in the soil and their infection of the tubers, observing that [[mycelium]] could survive the cold winter in the tubers. Based on these studies, he concluded that organisms were not being generated spontaneously.<ref name="Robinson"/>

====''Puccinia graminis''====
He did a thorough investigation on ''[[Puccinia graminis]]'', the pathogen that produces rust in wheat, rye and other grains. He noticed that ''P. graminis'' produced reddish summer [[spore]]s or "[[urediniospore|urediospores]]", and darker winter spores or "[[teleutospore]]s". He inoculated the leaves of barberry (''[[Berberis vulgaris]]'') with [[sporidia]] from winter spores of wheat rust. The sporidia germinated, leading to the forming of [[aecia]] with yellow spores, the familiar symptoms of infection on the [[barberry]]. De Bary then inoculated [[aecidiospore]]s on moisture-retaining slides and then transferred them to the leaves of seedling of [[rye]] plants. In time, he observed the reddish summer spores appearing in the leaves. Sporidia from winter spores germinated only on barberry. De Bary clearly demonstrated that ''P. graminis'' lived upon different hosts at different stages of its development.  He called this  phenomenon "[[heteroecism]]" in contrast to "[[autoecism]]", in which development takes place only in one host. De Bary’s discovery explained why the practice of eradicating barberry plants was important as a control for rust.<ref name="Robinson"/>

====Lichen====
De Bary also studied the formation of [[lichen]]s which are the result of an association between a fungus and an alga. He traced their stages of growth and reproduction and showed how adaptations helped them to survive conditions of drought and winter. In 1879 he coined the word "[[symbiosis]]", meaning  "the living together of unlike organisms",  in the publication "Die Erscheinung der Symbiose" (Strasbourg, 1879). He carefully studied the morphology of [[Mold (fungus)|mold]]s, [[yeast]]s, and fungi and basically established mycology as an independent science.<ref name="Robinson"/>